Question

If the oxyanion of the element X with the formula \[{\text{XO}}_2^ - \] is named with the suffix ‘ite’, what is the formula for the oxyanion of X using both the prefix ‘per’ and the suffix ‘ate’?
A.\[{\text{XO}}_5^ - \]
B.\[{\text{XO}}_3^ - \]
C.\[{\text{XO}}_4^ - \]
D.\[{\text{XO}}_2^ - \]

Answer 1

Hint: The naming of oxyacids is determined by the type of bonding that is present in between oxygen which ultimately depends upon the number of oxygen atoms present. Increasing 2 atoms will give us the required naming.

Complete step by step solution:
A prefix is always used before the name of a compound and a suffix is used after the name.
The formula for one of the oxyanions of the element X is \[{\text{XO}}_2^ - \] . The suffix used here is ‘ite’. When we increase one oxygen atom then the suffix used is ‘ate’ and the formula will become \[{\text{XO}}_3^ - \] .
Now if we increase one more oxygen atom then the formula will become \[{\text{XO}}_4^ - \] and the naming will be done using the prefix as ‘per’ and suffix as ‘ate’.

So, the correct option is C.

Additional information:
An oxyacid contains oxygen, hydrogen and at least one more element. They are acidic in nature that means at least one acidic hydrogen is present. The molecule can either dissociate to give hydrogen ion or to give hydroxide ion. Well known examples of oxyacids are sulphuric acid, nitric acid and phosphoric acid. A number of oxyacids can be formed with the same element by varying the number of hydrogen and oxygen which may lead to change in oxidation state of oxyacid.

Note:
The higher the oxidation state of oxyacid made by a certain element, the more acidic character it will possess. For example in the various oxyacids of chlorine the one with the most high oxidation number will be more acidic. The naming of anion of oxyacid is done by removing all the hydrogen from the acid.